Malgache, qui es-tn?' This question seeking the ancestry o f the Malagasy remains
unanswered five centuries after the debate on the proposed hypotheses of Malagasy origins
began. Historical, archaeological, linguistic and some genetic data suggest two major
sources o f ancestry: Africa and Indonesia, with minor contributions from Arabia, India and
China, but the evidence for the suggestions is sparse and inconclusive. All Malagasy,
irrespective of their ethnic backgrounds speak a common language, Malagasy, but
differences in physical appearance and culture suggests that they may have different
ancestral histories. The goals of this study are to utilize genetic variation present in the
Malagasy in conjunction with available data to reconstruct their prehistory and to provide
evidence confirming and/or refining existing theories concerning their prehistory. The
genetic profiles of eleven of the eighteen Malagasy ethnic groups, a South African Indian
and six African populations were compared at thirteen loci; eight autosomal and five Y
chromosomal. The markers include four STR loci each on the autosornes (HUMCSF1PO,
HUMTH01, HUMCD4 and an (AC)n repeat m the DRD2 gene) and on the Y chromosome
(DYS3.93, DYS19, DYS390 and DYS391), two Alu polymorphisms (CD4-/Uw and YAP)
and three RtLP loci within the DRD2 gene, Some o f these loci were used to derive
autosomal an-j Y chromosome haplotypcs, Population trees as well as principal component
analyses- bast-d ba the different data sets consistently revealed very close affinities between
the eleven Malagasy groups examined, The intermediate clustering of the Malagasy
between African and South Asians also reaffirms that these two groups have contributed
significantly to the Malagasy gene pool. Admixture estimates made using autosomal data
suggest that approximately 50% o f the Malagasy gene pool is derived from an African
source while Y chromosome data indicates an African contribution o f at least 60%.
Networks constructed using Y chromosome haplotypes identified a ‘Malagasy-specific’
haplotype cluster. A divergence time of 2864 years (95% confidence intervals, 1227 -
7472 years) is estimated for this cluster which is consistent with archaeological data
suggesting that the colonization of Madagascar occurred within the past 3000 years. Both
autosomal and Y chromosomal ihta from the present study supports a recent common
ancestry for the Malagasy from founders whose gene pool contained contributions from
Indonesians and Africans.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:wits/oai:wiredspace.wits.ac.za:10539/14767 |
| Date | 12 June 2014 |
| Creators | Morar, Bharti |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf |
Page generated in 0.0023 seconds